diff --git a/go/ql/lib/change-notes/2025-07-15-path-injection-sanitizers.md b/go/ql/lib/change-notes/2025-07-15-path-injection-sanitizers.md new file mode 100644 index 000000000000..004eb973de30 --- /dev/null +++ b/go/ql/lib/change-notes/2025-07-15-path-injection-sanitizers.md @@ -0,0 +1,5 @@ +--- +category: minorAnalysis +--- +* The second argument of the `CreateTemp` function, from the `os` package, is no longer a path-injection sink due to proper sanitization by Go. +* The query "Uncontrolled data used in path expression" (`go/path-injection`) now detects sanitizing a path by adding `os.PathSeparator` or `\` to the beginning. \ No newline at end of file diff --git a/go/ql/lib/ext/os.model.yml b/go/ql/lib/ext/os.model.yml index b4f074146b79..7d2070b53bac 100644 --- a/go/ql/lib/ext/os.model.yml +++ b/go/ql/lib/ext/os.model.yml @@ -28,7 +28,7 @@ extensions: - ["os", "", False, "ReadDir", "", "", "Argument[0]", "path-injection", "manual"] - ["os", "", False, "ReadFile", "", "", "Argument[0]", "path-injection", "manual"] - ["os", "", False, "MkdirTemp", "", "", "Argument[0..1]", "path-injection", "manual"] - - ["os", "", False, "CreateTemp", "", "", "Argument[0..1]", "path-injection", "manual"] + - ["os", "", False, "CreateTemp", "", "", "Argument[0]", "path-injection", "manual"] - ["os", "", False, "WriteFile", "", "", "Argument[0]", "path-injection", "manual"] # command-injection - ["os", "", False, "StartProcess", "", "", "Argument[0]", "command-injection", "manual"] diff --git a/go/ql/lib/semmle/go/security/TaintedPathCustomizations.qll b/go/ql/lib/semmle/go/security/TaintedPathCustomizations.qll index df601ce1eb84..ac6ea8c9835e 100644 --- a/go/ql/lib/semmle/go/security/TaintedPathCustomizations.qll +++ b/go/ql/lib/semmle/go/security/TaintedPathCustomizations.qll @@ -87,7 +87,7 @@ module TaintedPath { exists(DataFlow::CallNode cleanCall, StringOps::Concatenation concatNode | cleanCall = any(Function f | f.hasQualifiedName("path/filepath", "Clean")).getACall() and concatNode = cleanCall.getArgument(0) and - concatNode.getOperand(0).asExpr().(StringLit).getValue() = "/" and + concatNode.getOperand(0).getStringValue().prefix(1) = ["/", "\\"] and this = cleanCall.getResult() ) } diff --git a/go/ql/test/library-tests/semmle/go/frameworks/StdlibTaintFlow/Os.go b/go/ql/test/library-tests/semmle/go/frameworks/StdlibTaintFlow/Os.go index b27c5d1f47cb..859a3bbd3bd4 100644 --- a/go/ql/test/library-tests/semmle/go/frameworks/StdlibTaintFlow/Os.go +++ b/go/ql/test/library-tests/semmle/go/frameworks/StdlibTaintFlow/Os.go @@ -178,6 +178,6 @@ func fsAccesses() { os.ReadDir(path) // $ fsaccess=path os.ReadFile(path) // $ fsaccess=path os.MkdirTemp(path, part) // $ fsaccess=path fsaccess=part - os.CreateTemp(path, part) // $ fsaccess=path fsaccess=part + os.CreateTemp(path, part) // $ fsaccess=path os.WriteFile(path, []byte{}, 0600) // $ fsaccess=path } diff --git a/go/ql/test/query-tests/Security/CWE-022/TaintedPath.expected b/go/ql/test/query-tests/Security/CWE-022/TaintedPath.expected index 839d35f663ce..f5d86e68dbc6 100644 --- a/go/ql/test/query-tests/Security/CWE-022/TaintedPath.expected +++ b/go/ql/test/query-tests/Security/CWE-022/TaintedPath.expected @@ -1,25 +1,25 @@ #select -| TaintedPath.go:17:29:17:40 | tainted_path | TaintedPath.go:14:18:14:22 | selection of URL | TaintedPath.go:17:29:17:40 | tainted_path | This path depends on a $@. | TaintedPath.go:14:18:14:22 | selection of URL | user-provided value | -| TaintedPath.go:21:28:21:69 | call to Join | TaintedPath.go:14:18:14:22 | selection of URL | TaintedPath.go:21:28:21:69 | call to Join | This path depends on a $@. | TaintedPath.go:14:18:14:22 | selection of URL | user-provided value | -| TaintedPath.go:68:28:68:57 | call to Clean | TaintedPath.go:14:18:14:22 | selection of URL | TaintedPath.go:68:28:68:57 | call to Clean | This path depends on a $@. | TaintedPath.go:14:18:14:22 | selection of URL | user-provided value | +| TaintedPath.go:18:29:18:40 | tainted_path | TaintedPath.go:15:18:15:22 | selection of URL | TaintedPath.go:18:29:18:40 | tainted_path | This path depends on a $@. | TaintedPath.go:15:18:15:22 | selection of URL | user-provided value | +| TaintedPath.go:22:28:22:69 | call to Join | TaintedPath.go:15:18:15:22 | selection of URL | TaintedPath.go:22:28:22:69 | call to Join | This path depends on a $@. | TaintedPath.go:15:18:15:22 | selection of URL | user-provided value | +| TaintedPath.go:74:28:74:57 | call to Clean | TaintedPath.go:15:18:15:22 | selection of URL | TaintedPath.go:74:28:74:57 | call to Clean | This path depends on a $@. | TaintedPath.go:15:18:15:22 | selection of URL | user-provided value | edges -| TaintedPath.go:14:18:14:22 | selection of URL | TaintedPath.go:14:18:14:30 | call to Query | provenance | Src:MaD:2 MaD:3 | -| TaintedPath.go:14:18:14:30 | call to Query | TaintedPath.go:17:29:17:40 | tainted_path | provenance | Sink:MaD:1 | -| TaintedPath.go:14:18:14:30 | call to Query | TaintedPath.go:21:57:21:68 | tainted_path | provenance | | -| TaintedPath.go:14:18:14:30 | call to Query | TaintedPath.go:68:39:68:56 | ...+... | provenance | | -| TaintedPath.go:21:57:21:68 | tainted_path | TaintedPath.go:21:28:21:69 | call to Join | provenance | FunctionModel Sink:MaD:1 | -| TaintedPath.go:68:39:68:56 | ...+... | TaintedPath.go:68:28:68:57 | call to Clean | provenance | MaD:4 Sink:MaD:1 | +| TaintedPath.go:15:18:15:22 | selection of URL | TaintedPath.go:15:18:15:30 | call to Query | provenance | Src:MaD:2 MaD:3 | +| TaintedPath.go:15:18:15:30 | call to Query | TaintedPath.go:18:29:18:40 | tainted_path | provenance | Sink:MaD:1 | +| TaintedPath.go:15:18:15:30 | call to Query | TaintedPath.go:22:57:22:68 | tainted_path | provenance | | +| TaintedPath.go:15:18:15:30 | call to Query | TaintedPath.go:74:39:74:56 | ...+... | provenance | | +| TaintedPath.go:22:57:22:68 | tainted_path | TaintedPath.go:22:28:22:69 | call to Join | provenance | FunctionModel Sink:MaD:1 | +| TaintedPath.go:74:39:74:56 | ...+... | TaintedPath.go:74:28:74:57 | call to Clean | provenance | MaD:4 Sink:MaD:1 | models | 1 | Sink: io/ioutil; ; false; ReadFile; ; ; Argument[0]; path-injection; manual | | 2 | Source: net/http; Request; true; URL; ; ; ; remote; manual | | 3 | Summary: net/url; URL; true; Query; ; ; Argument[receiver]; ReturnValue; taint; manual | | 4 | Summary: path; ; false; Clean; ; ; Argument[0]; ReturnValue; taint; manual | nodes -| TaintedPath.go:14:18:14:22 | selection of URL | semmle.label | selection of URL | -| TaintedPath.go:14:18:14:30 | call to Query | semmle.label | call to Query | -| TaintedPath.go:17:29:17:40 | tainted_path | semmle.label | tainted_path | -| TaintedPath.go:21:28:21:69 | call to Join | semmle.label | call to Join | -| TaintedPath.go:21:57:21:68 | tainted_path | semmle.label | tainted_path | -| TaintedPath.go:68:28:68:57 | call to Clean | semmle.label | call to Clean | -| TaintedPath.go:68:39:68:56 | ...+... | semmle.label | ...+... | +| TaintedPath.go:15:18:15:22 | selection of URL | semmle.label | selection of URL | +| TaintedPath.go:15:18:15:30 | call to Query | semmle.label | call to Query | +| TaintedPath.go:18:29:18:40 | tainted_path | semmle.label | tainted_path | +| TaintedPath.go:22:28:22:69 | call to Join | semmle.label | call to Join | +| TaintedPath.go:22:57:22:68 | tainted_path | semmle.label | tainted_path | +| TaintedPath.go:74:28:74:57 | call to Clean | semmle.label | call to Clean | +| TaintedPath.go:74:39:74:56 | ...+... | semmle.label | ...+... | subpaths diff --git a/go/ql/test/query-tests/Security/CWE-022/TaintedPath.go b/go/ql/test/query-tests/Security/CWE-022/TaintedPath.go index e6a1c49f4c5b..a6519acea005 100644 --- a/go/ql/test/query-tests/Security/CWE-022/TaintedPath.go +++ b/go/ql/test/query-tests/Security/CWE-022/TaintedPath.go @@ -4,6 +4,7 @@ import ( "io/ioutil" "mime/multipart" "net/http" + "os" "path" "path/filepath" "regexp" @@ -63,6 +64,11 @@ func handler(w http.ResponseWriter, r *http.Request) { data, _ = ioutil.ReadFile(filepath.Clean("/" + tainted_path)) w.Write(data) + // GOOD: Sanitized by filepath.Clean with a prepended os.PathSeparator forcing interpretation + // as an absolute path, so that Clean will throw away any leading `..` components. + data, _ = ioutil.ReadFile(filepath.Clean(string(os.PathSeparator) + "hardcoded" + tainted_path)) + w.Write(data) + // BAD: Sanitized by path.Clean with a prepended '/' forcing interpretation // as an absolute path, however is not sufficient for Windows paths. data, _ = ioutil.ReadFile(path.Clean("/" + tainted_path))